The Mott certified cylindrical metal diffuser meets the certification requirements for the ASTM D892 & D6082 foam method.
Based on the geometrical shape alone, spherical stone diffusers produce larger bubbles, that tend to coalesce much easier forming larger
bubbles causing the foam to break more easily, thus giving slightly better results. Permeability and porosity of diffusers change over
time it is therefore recommended to test them periodically preferably after each use.
Lawler Part No. FM-3NC